Answer this question truthfully
### Question: What causes Congenital rubella syndrome?
### Response: Congenital rubella occurs when the rubella virus in the mother affects the developing baby at a critical time, in the first 3 months of pregnancy. After the fourth month, the mother's rubella infection is less likely to harm the developing baby.
The number of babies born with congenital rubella has decreased dramatically since the introduction of the rubella vaccine.
Pregnant women who are not vaccinated for rubella and who have not had the disease in the past risk infecting themself and their unborn baby.